1. Technical Field
Apparatuses and methods consistent with exemplary embodiments relate to a host, and more particularly, to a host for controlling the frequency of an operating clock signal of a display driver integrated circuit (IC) based on a data transmission timing control signal output from the display driver IC, a system including the same, and a method of operating the system.
2. Description of the Related Art
Mobile devices including a liquid crystal display (LCD) panel drive the LCD panel in various modes including a video mode or a command mode. Mobile Industry Processor Interface Display Serial Interface (MIPI® DSI) is a related art display standard for portable electronic devices.
MIPI supports two display modes, i.e., the video mode and the command mode. In the command mode, the start of frame data transmission from a host is controlled by a tearing effect (TE) signal. In the video mode, frame data is transmitted from the host to a panel in real time.
When a still image is displayed on a display panel, a display driver IC periodically reads the still image from a frame buffer included in the display driver IC and displays the still image on the display panel, which is referred to as a panel self-refresh. At this time, the display driver IC performs the panel self-refresh using a clock signal output from a resistor-capacitor (RC) oscillator. Since the RC oscillator is sensitive to temperature variation, the frequency of the clock signal may deviate. This deviation causes electromagnetic interference (EMI), which interferes with the operating frequency of other devices, e.g., a touch screen, a stylus pen, etc.
When the display driver IC transmits a TE signal to the host in the command mode, the host transmits frame data to the display driver IC based on the TE signal. The TE signal is used to prevent tearing or screen tearing. The tearing or screen tearing is a visual artifact appearing when image data corresponding to at least two different frames is displayed simultaneously on a single screen on a display panel.